Laura Peeters

1 General Introduction | 13 there is no cure available, current treatment focuses mainly on slowing down disease progression (e.g. using corticosteroids [19]) and symptom management (e.g. physical therapy, nocturnal ventilation, cardiac medication [21]). Box 1 Symbionics project The studies performed in this thesis are part of the Symbionics program (project 2.1). The aim of this project was to develop dynamic support for trunk and head for persons with neuromuscular disorders to assist them when performing daily activities. To achieve this goal, several Dutch universities (i.e. University of Twente, Vrije Universiteit Amsterdam and Radboud university medical center) have worked closely together. Both passive and active trunk and head supports were developed with the vision that these supports should be close to the body and should be as inconspicuous as possible. The passive supports assist to balance the trunk or head with the use of springs, so the user needs less muscle effort to move. The active supports provide additional assistance as muscle strength decreases further by the use of actuators and control strategies embedded with the spring-based mechanism. The Radboud university medical center focused on the clinical perspective. Insight was gained on trunk and head function during seated arm tasks in the user groups to specify requirements for the supports. The Vrije Universiteit Amsterdam was responsible for design and development of prototypes and evaluation. Expertise of the University of Twente was on the control interfaces and control methods for the active supports.